DGM (Dutch-German Mennonite)

Inheritance: autosomal dominant
Genes: SLITRK1

Tourette syndrome
TS
Tourette disorder

Tics
Behavior disorder
Echolalia
Repetitive motor tics
Stuttering
Blinking

Gilles de la Tourette Syndrome

Clinical Characteristics

General description (for patients):

Patients can have multiple involuntary motor and vocal tics.  This often takes the form of grunts, stuttering, coughing, repeated touching of body parts, repeated words, inappropriate language, blinking, and facial grimacing.  Only a small percentage has a family history of similar relatives, and three-quarters are male.  Many cases are probably so mild that medical attention is not sought.  Individuals tend to be highly focused and sometimes seem obsessive-compulsive about tasks.  Onset almost always occurs by 10 years of age with symptoms generally persisting throughout life.

Medical description:  

Tourette’s syndrome is an involuntary movement disorder, sometimes with inappropriate language, echolalia, and coprolalia.  Individuals tend to be obsessive-compulsive and are sometimes diagnosed as learning disabled.  Some have suggested that attention deficit and hyperactivity may be early signs but clearly these do not make the diagnosis.  There is no increased history of major psychiatric disorders in this condition.  Because many cases are so mild and the clinical phenotype so variable, it is possible that GTS is a spectrum of disease for which we lack precise criteria.

Genetics:

Multiple pedigrees suggest autosomal dominant inheritance but penetrance based on current criteria is low. A sex-influenced, semi-dominant susceptibility gene with multifactorial modification has been proposed but no molecular mutation has been found.  Sequence variants in the SLITRK1 gene on chromosome 13 (13q31) have been found in a minority of patients but a variety of other loci on multiple chromosomes have been implicated.  A large Dutch German Mennonite pedigree has been reported in Alberta, Canada.

Treatment:

No treatment is known beyond neuroleptic drugs for behavior modification.

Prognosis:

Mild cases do well without notable disabilities but more serious cases may exhibit embarrassing activity in public.

Ancillary treatments and support:

Behavior specialists.

Specialists and specialty centers:

Psychiatrist, neurologist, behavior therapists.

References:

Kurlan, R., Behr, J., Medved, L., Shoulson, I., Pauls, D., Kidd, J.R., and Kidd, K.K.:  Familial Tourette’s syndrome: report of a large pedigree and potential for linkage analysis.  Neurology 36: 772-776, 1986.  PubMed ID: 3458031

Kurlan, R., Behr, J., Medved, L., Shoulson, I., Pauls, D., and Kidd, K.K.:  Severity of Tourette’s syndrome in one large kindred: implications for determination of disease prevalence rate.  Arch. Neurol. 44: 268-269, 1987.  PubMed ID: 3469941

Tourette Syndrome Association International Consortium for Genetics:  Genome scan for Tourette disorder in affected-sibling-pair and multigenerational families.  Am. J. Hum. Genet. 80: 265-272, 2007. PubMed ID: 17304708

Resources:

Tourette Syndrome Association